Electric lighting.



- P. U. HEWITT.

ELECTRIC LIGHTING.

APPLICATION FILED JAN.18, 1908'.

1,079,343, Patented Nov. 25, 1913.

Euler M02;

7 WWW Jul fllioriwg.

STATES PA ENT OFFICE.

PETER COOPER HEWITT, OF RINGWOOD MANOR, NEW JERSEY, ASSIGNOR, BY MESNEASSIGNMENTS, TO COOPER HEWITT ELECTRIC COMPANY,'OF HOBOKEN, NEW JER-SEY, A CORPORATION OF NEW JERSEY.

ELECTRIC LIGHTING.

Specification of Letters Patent. Original application filed April 5,1900, Serial No. 11,608.

Patented Nov. 25, 1913. Divided and this application filed January 18,

1908. Serial No. {111,384.

To all whom, it may concern Be it known that I, PETER COOPER HEW- ITT, acitizen of dent of Ringwood Manor, county of Passaic, State of NewJersey, have invented certain new and useful Improvements in ElectricLighting, specification.

My invention relates to improvements in electric lighting apparatus inwhich electric energy is employed for producing light through the agencyof vapors and gases.

In another application filed by me April 5, 1900, Serial Number 11,605,Ihave described a form of vapor or gas electric lamp in which a goodconducting path is formed for currents of moderate potential and whichis capable of regulating within itself the current flowing, so that itis suitedfor general use upon-commercial circuits. One of the materialssometimes employed for the light-emitting medium in the lamp referred tois mercury vapor. The spectrum of mercury is deficient in red rays, andfor some classes of lighting an abundance of red rays is desirable.

My present invention aims to combine with a lamp having a vapor or gasyielding a spectrum lacking certain rays, another lamp which willproduce the rays not produced by the first. For convenience ofdescription, it will be assumed that a lamp 1s employed in which themain portion of the light is produced by mercury vapors and that it isdesired to supplement it with a spectrum having a sutficient abundanceof red rays. I accomplish this result by combining or associating withthe mercury vapor, a vapor or gas such, for instance, as nitrogen,helium or argon which also is to be acted upon by the electric currentso as to produce red rays in addition to such other rays as arecontained in its spectrum, thereby' supplying the deficiency of themercury spectrum. This may be accomplished In various ways. Forinstance, the mtrogen may be included in a lamp' structure similar tothat employing the' mercury and located in such proximity thereto as toproduce the desired resultant efl'ect. Another way of accomplishin thedeslred result is to combine with sucl x a lamp as the mercur'y vaporlamp an ordinary form of mthe United States, and resiof which thefollowing is a candescent lamp connected inseries or parallel therewithbut so located as to have its rays mingle with those of the mercurylamp. I desire to have it understood, however, that the invention is notrestricted to combining the lamp giving the supplemental rays with avapor lamp having mercury as the lightemlttmg substance but generallycombining with any form of vapor lamp, such as referred to in myapplication Serial Number 11,605, of 1900, a supplemental light-emittingbody yielding the desired additional rays. In this application specificclaims are not made to the combination of a vapor lamp with the ordinaryform of incandescent lamp as that forms the subject of anotherapplication'.

The accompanying drawing illustrates a system of illumination whereinthe two c0- operating lamps are joined in parallel to the opposite sidesof the work circuit.

Referring to the drawing a tube, 1, is

shown as containing two electrodes, 2 and 5. The electrode, of a solidbody which is conducting under proper conditions, consists, in thisinstance, of a body of mercury. Leadingin wires, 7 and 8, respectivelyconnect with the two electrodes through the walls of the glass. to, orin suitable relation with, the tube 1, is a second tube 11, likewiseprovided with electrodes 12 and I stance I have shown the tube 11 as astraight vertical tube with a bulb or enlargement 14 at its upper endand surrounded spirally by the lamp 1. Manifestly the straight tube, 11,might be the tube containing the electrodes 2 and 5, one solid and theother of mercury or the like, while the spiral tube surrounding it mightbe the one containing nitrogen or other gas or vapor for adding certainrays to the spectrum.

To render the lamps suitable for general use upon commercial circuits,it is desirable that they should receive currents under the influence ofmoderate electroinotive forces and possess within themselves thecapacity of self-regulation with respect to the amount of currentreceived. I have found that lamps may be made which will conduct currentat low potentials and within req- 2, is here shown as consisting.

Adjacent 15. In the present in-.

while the electrode. 5

uisite limits proportional to the electromotive force applied in suchmanner as to be self-regulating and highly eflicient. The general planof manufacture is to thorougly cleanse the tubes or receptacles byalkalis and proper acids, then exhaust them, by passing electriccurrents through them during the process of exhaustion. The

lamp is further treated by properly heating the electrodes and creatingsuch chemical reactions therein as would be liable to take place in useand drawing off the impurities anddeleterious materials and subjectingthe lamps while in the process of manufacture to the class of currentswith which they are to be operated and introducing within the tubes theproper'amount of vapor or lightyields red rays; other substances alsoyield red rays, for instance potassium, lithium,

hydrogen, etc. The two lamps may be placed upon the same circuit andeither in series or parallel, as may be desired under given conditions,and by being properly located with reference to each other, the resultant effect is a brilliant light containing all of the desired rays.

Instead of placing the lamps as shown in the drawing, the tubes may becurved, one being placed within the are of the other. The chamber 4,shown in the drawing, is not always required but is frequentlydesirable, particularly in connection with lamps using mercury as acooling and impurity containing chamber. It is usually desirable that itshould be out of the vapor path.

For the purpose of starting lamps of this character it is usuallydesirable to employ an initial higher potential for producing within thelamp such a condition on the part of the vapor as will cause it toreceive currents of the potential with which it is designed to beoperated. To accomplish this any convenient arrangement of circuitsmaybe employed and in the drawing, I have illustrated one organizationof such circuits in connection with a difi'erent arrangement of lamps.In this instance the lamp 11, is in the form of a spiral surround ingthe lamp 1. These lamps are connected across the main circuit conductors24, 25, by conductors 20, 21. In the conductor 20, there is included thecoil 22, of a suitable spark-coil or reactive device, the core of whichis represented at 23. A conductor 20, including a switch 27, leads fromone ternnnal of the coil 22, to the main conductor 25, the arrangementbeing such that the coil 22, may be placed in closed shunt across thecircuit 24-, 25. A suitable condenser 28, of any desired form isconnected in shunt around the switch 27. hen the switch is closed anelectric current is passed through the coil 22, and upon breaking theconductor 26, a high difference of potential is established at theterminals of the lamp, and the result of this is to create such acondition on the part of the vapor column as to cause the current fromthe conductors 24 and 25, to flow easily through the lamp and operateit. A separate starting device may be provided for each lamp if desired.The two lamps may be connected in series if desired. It is frequentlydesirable to relieve the lamps from static charge during the ap-vplication of the starting current by means of a conducting bandsurrounding the lamp near one electrode and connected by a conductorwith the leading-in wire at the other terminal of the lamp. I have foundthat by placing a conductor such, for instance, as a band of foil orother suitable material, near the electrode 5, and connecting it by aconductor 13, with the leading-in wire 7, the starting currents are moreeffective. Where two separate lamp structures are employed, a similardevice will be used with each lamp. As the starting device is liable tooperate upon only one lamp at a time it may be desirable to use somesuch arrangement of circuits as indicated in the drawing, in which aswitch 30, is introduced into the conductor 20. This switch may beconnected with either of two contact points 31 and 32. connectedrespectively with the two lamps 1 and 11. When in contact with the point31, the starting device is applied to the lamp 1, and when that lamp hasbeen started a switch 33, my close its connections through a conductor35, including a resistance 34: to the main line 24. By moving the switch30, into contact with a point 32, the line 20, is connected with thelamp 11, which may then be started. A switch 36, may be used to placethe lamp 11, in connection with the conductor 35.

This application is a division of my application Serial Number 11,608,filed April 5, 1900. Of the said parent application there is alsoanother divisional application Serial Number 105,723, filed May 3, 1902.

I claim as my invention 1. In a system of electrical distribution, thecombination with a source of direct current, a plurality of vaporelectric devices,

each comprising an exhausted container and suitable electrodes therein,and means for connecting said devices in parallel across said mains, ofmeans for operating said lamps in parallel, said means including a reistance in series with one of said devices,

- suit-able electrodes therein, and means for s1stance in series withone of said and an inductance in series with another, together withmeans for utilizingsaid inductance for starting each of the devices.

2. In a system of electrical distribution, the combination with a sourceof direct current, a plurality of vapor electric devices, eachcomprising anexhausted container and connecting said devices in parallelacross said mains, of means for operating said lamps in parallel, saidmeans including a redevices,

and an inductance in series with another, 7

together with means ,for utilizing saidinductance for starting eachofthe devices,

and means for interchanging said resistance and said inductance betweensaid devices.

Signed at New. York, in the county of New York, and State of New York,this 17th day of January, A. D. 1908.

PETER COOPER HEWITT.

Witnesses:

WM. H. OAPEL, GEORGE H. S'rooknmnon.

